#include "mystdio.h"
#include <unistd.h>
#define myfile "test.txt"

int main()
{
    _FILE*fp=_fopen(myfile,"a");
    if(fp==NULL) return 1;

    const char*msg="hellow world\n";
    int cnt=5;
    while(cnt){
        _fwrite(fp,msg,strlen(msg));
        sleep(1);
        cnt--;
    }
    _fclose(fp);
    return 0;
}
